When people like Martin Luther King Jr. and Emma Tenayuca fought for better conditions for their own (African Americans and the working class), they helped to raise awareness of how unfair the situation was for many people.
Generally speaking, besides achieving, eventually, their goals of equal rights or better conditions, individuals and organizations contribute not only for gaining ground on the important matters, but also for raising awareness to issues and creating new important leaders or organizations that fight for civil rights and equality.